LUSTRE · Ultra-fast Laser Surfacing of Teeth for Resistance to Erosion

Ultra-fast Laser Surfacing of Teeth for Resistance to Erosion

The LUSTRE project (Ultra-fast Laser Surfacing of Teeth for Resistance to Erosion) applies the latest laser technologies and materials science developments to resolve the problem of tooth enamel wearing away over time. The LUSTRE project’s objective is to create a handheld, easy-to-use application, incorporating a pressure driven fluid flow device and a pulsed laser, which a dentist could use to repair an eroded enamel surface. In period 2 the LUSTRE project consortium, consisting of the University of Leeds, University of St. Andrews, University of Bari, M2, GTS, ICMEA and LaserInn, made strong progress in the following areas: 1. Improvements to the mode-locked laser, based on a low cost glass gain medium 2. Development of a fully enclosed, potentially commercialisable laser, tailored for surfacing of teeth 3. Modifications to the materials delivery device for the deposition of thicker gels 4. Assembly of the various components into a single application and integration testing In 1) adjustments to the mode-locked laser cavity at the University of St. Andrews, using a low cost glass gain medium instead of a more expensive crystal, were made to increase the efficiency of the mode-locking. These changes resulted in a decrease of the pulse duration from 500 fs to 150 fs. This has the benefit of further minimising the accumulation of the heat, generated in the bonding process, and thus alleviating the risk of tissue damage. In 2) a compact, fully-enclosed, mode-locked laser was developed by M2 to provide a laser output with the optimum laser parameters (wavelength of 1 micron, average power of 0.8 W and pulse duration of 500 fs) for bonding the mineral-based compounds to the eroded enamel. The laser output was coupled into an optical fibre by the University of Leeds, thus delivering the beam to the materials delivery device. ICMEA made modifications in 3) to the actuation mechanism in the materials delivery device to allow it to deposit thick, viscous gels, as well as the thinner gels that had been used earlier in the project. Homogeneous layers of viscous gels were successfully deposited on enamel surfaces following these improvements. In 4) the output from the mode-locked laser developed in 2) and the delivery device improved in 3) were assembled into the final application. The integration tests demonstrated the application’s ability to deliver a precise quantity of gel and repair a 2 mm x 2 mm, 50 microns deep area of damaged enamel in a few minutes. Toxicity and brushing tests at the University of Bari showed that the newly bonded layer was safe and resistant to friction. The LUSTRE project has thus delivered an in-situ prototype application for rapid photo-induced restoration of tooth enamel, using a non-toxic biocompatible mineral. Potential impact and use The application developed could potentially be used in dentistry practices, leading to a significant reduction in treatment time and thus cost saving for dentists. Further collaborations based on the LUSTRE project for emerging pre-clinical research are already underway. Socio-economic impact This research will be of interest to chemicals companies, laser manufacturers and clinical dentists. More information is available at http://www.lustre-project.eu/

Data: CORDIS, © European Union